The correct answer is A.
I hope I've helped!
Hey there! :D
A verb phrase is a phrase that defines the action. It contains the verb in the sentence.
"walked" is the verb, so "A" Have walked, is the answer.
I hope this helps!
~kaikers
Answer:
Explanation: Ecological barriers are natural borders between two ecosystems such as a desert, rivers, or mountains.
Okay a dichotomous key is where you basically create a key to where others find out what kind of animal is the one they're trying to find out. I would suggest using Google to look up examples. It would probably benefit you the most.<span />
Water molecules would probably be it since they are in water and they are made up of two hydrogen and one oxygen.